Character mouth setup

Hi cg artist.Ok I have a problem on making a character talking.I’ve been finish creating my character and parent it to a rigged armature.The tongue
parented to the head bone,the teeth with the gum (gencive in french maybe) and the gum with the head bone so they are not a part with the character.My problem is how so setup the lipsync if the tongue or the gum is not part with the character.Let say that my character want to say the word “L” or " THE" where the tongue, the teeth and the character lips need to be deform.I want to know how this could be achieve in the IPO editor with just one key setup,where all this part come into play simultanoeusly.Can this be achieve or I have to manually for exp:(rotate the gum, deform the tongue) for letter “L” etc.